By Brad Haynes and Hugh Bronstein BUENOS AIRES, Jan 27 (Reuters) - Argentina set monthly limits on dollar purchases on Monday, widening the gap between the official and parallel exchange rates with an erratic currency policy that has battered the peso and rattled global financial markets. By limiting the purchases of U.S. dollars to a fifth of a worker's monthly wages, the government revived doubts about its commitment to a more open currency market under measures announced on Friday. The concerns circling the peso, which posted its biggest daily drop in a decade last week, added to fears of an emerging-market selloff hitting currencies from the Turkish lira to the Polish zloty. Argentina's ostracism from international credit markets since a 2002 debt default has limited the risks to the global financial system. However, the plunging peso could hurt trade with neighbors such as Brazil, whose currency closed at a five-month low on Monday. Argentina's central bank stabilized the official peso by pumping $100 million of its waning reserves into the interbank market. But private traders wary of the government restrictions weakened the peso nearly 4 percent in parallel trading. Due to excess demand for dollars, the peso trades on the parallel black market at a discount of more than 40 percent to the tightly controlled official exchange rate. "This is a relief, but it is not freedom. In practice, it gives just a little escape," said economist Rodolfo Rossi in Buenos Aires. "The pressure on the (black-market peso) is going to continue." The local currency weakened on the black market to 12.15 pesos per U.S. dollar, while the official exchange rate was unchanged at 8 per dollar in thin trading. Last week, the official peso slid nearly 20 percent as investors scrambled to make sense of the new currency regime. The rapid depreciation has raised credit risks for Argentine banks, insurers and companies with foreign debts, analysts from Moody's Investors Service warned in a research note to investors. "It remains unclear what policies the government plans to pursue to address the underlying causes of capital flight, curb inflation and restore investor confidence," the ratings agency said in a statement. "Hence, Argentina's credit quality will likely continue to face negative pressure." Moody's forecast a further 50 percent devaluation of the peso by the end of the year, with price pressures from imports pushing inflation upward to over 30 percent in 2014, from what is already one of the world's highest inflation rates. Argentine officials were quick to dismiss such risks. "There is no reason that the exchange rate should distort consumer prices," said Cabinet Chief Jorge Capitanich in a press conference detailing the new regulations. "Lots of businesses just raise their prices out of uncertainty." Shopkeepers over the weekend hurriedly replaced price tags on imported items, from Cuban cigars to Asian televisions. The price surge followed the government's decision to lift two-year-old restrictions on Argentines buying foreign currency, allowing savers access to coveted U.S. dollars. The relaxation of controls came as the central bank's foreign exchange reserves dipped under $30 billion - a level suggesting its interventions in support of the anemic peso had become unsustainable. Allowing average wage-earners to access U.S. dollars should pressure reserves as well, because the central bank is the economy's main source of foreign exchange. Conditioned by previous financial crises to hold savings in dollars, Argentines are obsessed with the greenback. The currency controls regime ending on Monday forced many people to go to the black market for dollars to protect against the weak peso and fast-rising consumer prices. INFLATION RISKS Consumer prices rose about 25 percent in 2013, according to private analyst estimates. Official data, which many economists dispute, clocks inflation at less than half that rate. A new government consumer price index, ordered by the International Monetary Fund, is expected to be unveiled next month. While inflationary, President Cristina Fernandez's policies were seen by most voters as the key to economic recovery from the 2002 debacle. She easily won re-election in 2011, promising deeper market interventions and more stimulus spending unencumbered by inflation targeting. The effect of peso volatility on other countries' markets should be limited by the fact that Argentina has been unable to issue international bonds since its 2002 sovereign default. Since then, the government's unorthodox policies - underscored by its 2012 seizure of energy company YPF - have kept all but the most risk-hungry investors at bay. The peso's recent slide added to risk aversion in global financial markets, but foreign officials played down concerns. "The troubles in Argentina today find a European Union that is much more solid and a euro that is much more solid and a better ability to deal with this kind of concern," Italian Prime Minister Enrico Letta told journalists on Monday. Consumer prices remain a big worry on the streets of Argentina, but the issue has not sparked mass protests lately. Tensions may rise in the coming weeks as labor unions demand that pay increase in line with private inflation estimates. If Argentina suffers 30 percent inflation this year, as private analysts expect, it would mark the fastest rate since the 2002 crisis, when inflation reached 41 percent. Fernandez has mentioned neither consumer prices nor the peso's plight in recent speeches, leaving her cabinet to announce policy changes. The next presidential election is in 2015, with Fernandez constitutionally barred from a third term.